Method and means for making nut blanks



Jan. 29, 1946. w cox 2,393,850

METHOD AND MEANS FOR MAKING NUT BLANKS Filed Dec. 19, 1944 5 Sheets-Sheet 1 5TATION*6 Jan. 29, 1946.

R. L. WILCOX METHOD AND MEANS FOR MAKING NUT BLANKS 3 Sheetsheet 2 Filed Dec. 19, 1944 Qw zs m gnaw-m i, Me

Jan. 29, 1945. WILCQX 2,393,850

METHOD AND MEANS FOR MAKING NUT BLANKS Filed Dec. 19, 1944 I s Sheets-Sheet s Patented Jan. 29, 1948 I UNITED" STATES PATENT OFFICE I METHOD AND MEANS MAKIhG i v "are mannerisms :n:

chine Company, Waterbury, Conn. corporation of Connecticut Application December 19, 1044. Serial No. 588,801

21 Claims. (Cl. 10-") This invention relates to a method of forming nut blanks, and to a new and improved machine for carrying out the novel method. Although not limited to a particular form of nut blank, I have illustrated my improvements as applied to a nut having a lower portion of polygonal shape and an upper portion having a recess therein-sun rounded by a skirt which, as shown, is cylindrical in form. v

As illustrated. the nut blank is formed from a piece of solid bar stock from which a workpiece is cut at the beginning of the operation. 'This workpiece is then fed through the machine by suitable transfer mechanism, where it is acted upon at a number of stations in sequence at which various operations are performed on the workpiece until the finished blank is produced serves to support or carry a plurality of dies, and

a reciprocable gate, movable toward and from the die block, carries suitable tools to cooperate with the dies to perform the desired operations upon the workpiece.

One feature of the present invention is the formation of finished and relatively sharp shoulders upon the workpiece as it passes through the machine, and more particularly at the station at which the hexagonal faces are formed upon the workpiece. This operation is performed in a die movably mounted in the die block, so that after the workpiece has been forced into the die opening by a suitable punch, the punch and die may be moved forward together, thus forcing .the nut against a suitable tool, which operation enables the filling out of the corners of the polygonal portion of the nut adjacent the bottom of the cylindrical skirt. As will be apparent from the description as it proceeds, this filling out of the corners on the outer surface of theworkpiece enables the latter at a subsequent station to be held by these corners while further operations are performed thereon.

A further feature of the invention is the novel method of and mechanism for piercing the workand designed to carry out my improved process;

Fig. 2 is an enlarged view of the cooperating tools and dies at two of the stations in the machine;

gig. 3 is a sectional view on line 3-3 of Fig. 2; m

Figs. 4 to 9, inclusive, are views, Par ly in elevation and partly in section. showing the workpiece as it appears at various stations in the machine after various operations are performe thereon.

In Fig. l of the drawings I have shown a machine of the'header type comprising a die block ll mounted in the frame ll of the machine, the die block being supported by a backing member if. Movably mounted in the frame ii is a gate ll designed to be reciprocated to and from the die block, as is usual in machines of this type.

the gate being provided with a number of tools which cooperate respectively with a plurality of dies in the die block, aswill be hereinafter explained.

At one end of the machine, designated on th drawing as station I, a die It is mounted in the die block Ill, this die being provided with an opening I! throughwhich a piece of bar stock it may be inserted so that the end of the piece of stock will protrude from the die to be severed by a cut-off tool ll, this severed end becoming the workpiece 18 shown in Fig. 4- of the drawings.

This workpiece is then advanced by suitable transfer mechanism (not shown) to station #2. at which station a suitable die 20 is mounted in a die holder 2i and held against movement by a backing sleeve v22. This die 2i! is provided with an opening 23 within which is a stationary tool 24 closing the rear end of the opening.

In the gate ll opposite the die 20 is mounted a punch .holder 28 within which is movabiy mounted a punch 26. the latter being urged for wardly by a spring 21. As will be apparent from Fig. 1 of the drawings, when the gate is moved toward the die block, the workpiece which has been cut from the length of stock will be forced vwill extend at right angles to the axis of the blank. The opening within the die 20 may be slightly coned at its rear end, or the end adjacent the tool 24, so that the rear face of the workpiece may be slightly coned at this point, as shown more particularly at 28 in Fig. 5, on the workpiece 29. This figure of the drawingsillustrates the shape of the workpiece after being acted upon at station #2.

At station #3 in the machine a die 30 is secured in a holder 3| movably mounted in the die block l and urged outwardly by a relatively strong spring 32, the die holder 3| beingprovided with a shoulder 33 abutting against a cooperating shoulder on a fixed sleeve 34 to limit forward movement of the die and die holder by the spring 32. The die 30 is also provided with an opening into which projects a punch or tool 35 secured to a tool holder 36, which is designed to be advanced by a pin 31 to eject thework from the die after the completion of a forward stroke of the gate.

As will be apparent from Fig. 1 of the drawings, the die 30 is provided with an opening which is slightly flared at its inner end, and the outer end of the punch or tool 35 is of the shape of a frustum of a cone, and is of smaller size than the die opening so that the blank at this station will be indented and a skirt formed thereon around the indentation.

The gate at this station is -provided with a punch 39 mounted in a punch holder 40, the punch being provided with a recess 4| in its front end and an opening 42 communicatin with this recess in which is movably mounted a pin 43 urged forwardly in the gate by a spring 44, which surrounds an enlarged head 45 on the pin and acts. against the shoulder 46.

Two operations are performed upon the workpiece at this station in the machine, as shown in Figs. 6 and 7 of the drawings. It will be understood that when the gate is in its rear or retracted position, the pin 43 will be projected forwardly from the punch 39 by the spring 44. As the workpiece 29 is brought to this station by the transfer mechanism, and the gate is moved forwardly toward the die, this pin will engage the workpiece and hold it during withdrawal of the transfer mechanism. Upon further movement of the gate the punch 39 will engage the workpiece and force it into the die opening, the retraction of the pin being permitted by the spring 44'. Upon further advance of the gate, and after the punch has made contact with the outer surface of the die 30, the punch and die will be moved rearwardly together, the die opening'belng closed by the punch, until the parts are in the position shown in Fig. 1, in which the workpiece has been moved against the then stationary tool 35. r

The workpiece will at this time be in the form 'shown'at 41 in Fig. 6. It will be noted that the lower end of the workpiece has been coned or tapered, as shown at 48, by being forced into the recess in the face of the punch, and that the Opposite face of the workpiece has been indented and a relatively deep recess formed therein by the tool 35, the wall or skirt portion 49 about this recess being flared outwardly to some extent beyond the wall of the body portion of the blank. i

The gate is now withdrawn or retracted and the knock-out pin 3'! advanced to cause the tool or punch 35 to strip the workpiece from the die. During thi stripping operation the flared wall 49 of the workpiece is drawn to cylindrical shape,

, as shown at 50 in Fig. 'l, the blank being shown at El in this figure in the form in which it comes from the die. It may also be noted that the recess 52 in the blank at this stage in its manufacture is somewhat deeper than as shown in Fig. 6 at the completion of the previous step.

The workpiece or blank is now moved to station #4. At this station a suitable punch 54 is mounted in a punch holder 55 in the gate l3, the punch 54 being of polygonal shape and provided with an indenting projection 56 upon its forward end. A die holder I5! is movably mounted in the die block ID at this station, the die holder being provided with a shoulder 58 designed to abut a cooperating shoulder 59 upon a part of the block to limit forward movement of the holder.- A relatively strong spring 60 urges the holder forwardly in the die block against the shoulder 59. Secured in the die holder 51 are cooperating die members GI and 62,

these members having cooperating openings the outer one of which is hexagonal in form and the inner one circular in form. Extending into the openings in the die members 6| and 62 is a tool 63 secured in a tool holder 64 designed to be moved forwardly by a knockout pin 65. It will be noted from Fig. 2 of the drawings that the punch or tool 63 is provided with a tapered portion 86 adjacent its end, and an indenting pro- Jection 61 upon its end, so as to perform proper operations upon the workpiece at thi station.

When the workpiece has been carried to station #4 and the gate is moved forwardly, the punch 54 forces the workpiece 6| into the openings in die members 8| and 62. During the initial part of this movement the die holder 51 is held in its outward position by the spring 60. However, when pressure is applied to the workpiece by the punch 64, tending to expand it into the hexagonal die opening and form polygonal faces upon the the polygonal faces at the base of the skirt; With the use of a movable die, however, when the metal contacts the faces of the polygonal opening the die travels with the punch and causes the metal to flow more readily to these corners when the workpiece is carried against the stationary tool 63.

Also at this station it will be apparent that indentations are-made in the forward face of the workpiece by the punch, and also at the bottom of'the recess by the tool 63 so as to leave a web portion therebetween to be later punched out to form an opening through the blank.

The workpiece orblank, as it is formed at station #4, is shown in Fig. 8 of the drawings, and it will be noted that, as shown in'this figure, the blank is provided with a polygonal lower portion 68 having relatively flat faces thereon, and an upper cylindrical skirt portion 69 with relatively sharp, well-fllled'corners 10 between these portions. Moreover, it will be noted that the m terior of the wall 39 surrounding the recess 'II is assasso end than at its base. The exterior surface of. the

skirt or wall 88 is, however, substantially parallel with the axis of the recess, thus rendering the wall itself slightly thinner at its upper end than at its lower end. It will also be noted that indentations 12 and 18 are formed in the body portion of the nut, leaving the web" therein.

The workpiece is now transferred to station #8, shown in Figs. 1, 2 and 3 of the drawings. At this station a piercing punch 18 is secured in the gate I8 so as to be moved with the gate toward the die block. In the die block at this station is provided a die 18 secured in a die holder 11 against a backing block 18. As shown in Fig. 3,

the die may be provided with shoulders 18 abutting cooperating shoulders 88 on the die holder to prevent the die being moved forwardly during the operation of the machine. The die is provided with an opening 8I of the proper shape to receive the workpiece shown in Fig. 8, the opening having a polygonal outer portion and a cylindrical slightly tapered inner portion. Reciprocably mounted in the backing block 18 is a knock-out sleeve 82, this sleeve being mounted in a sleeve holder 83 urged-rearwardly within the block 18 by a spring 84. The sleeve holder 88 is provided with .a head 88 againstwhich impinges a knock-out pin 88 to drive the holder and sleeve forwardly at the proper time to eject the nut from the die.

This sleeve is provided at its lower end with a reduced cylindrical portion 81 designed to enter the recess ll of the blank, and it will be understood that the opening in the sleeve is of sufllcient size to freely receive the end of the piercing punch 15. Also at the lower end of the sleeve 82 are provided a pair of oppositely disposed elongated openings or slots 88, and beyond these slots this sleeve is provided with a dischargeopening 88 registering with an opening 8I in the sleeve holder 88, an opening 82 in the backing block 18, and an opening 88 in the die holder 11 to permit ejection of the slugs pierced from' the workpiece at this station.

Secured inthe die member 18 and extending through the openings 88 in the sleeve 82 are a pair of pins 84, these pins being disposed at the outer ends of the openings 88 when the knock-out sleeve is in its rearmost position. The die holder 11 may be held in place by means'of the set screw 88 (Fig. 3). Within the sleeve 82 .is a-plug 88 having a beveled end 81 designed to assist in election of the slugs from the sleeve, as will be hereinafter explained.

When the workpiece or blank has been moved to station #8, and is forced into the die opening. 8| by the piercing punch 18, it is held in position in the opening by the shoulders 18, which, as has been previously described, are sharply formed and well filled out for this purpose No part of the pressure of the punch against the blank is borne by the sleeve, 82, the-blank being held in the die opening by the engagement of these external shoulders. Further advance of the punch serves to pierce the blank or out the web 14 therefrom in gated slots 88 through which the pins 84 proiect. Upon a subsequent operation of the machine, when a second slug88 is pierced from a blank, the first slug will be forced ,beyond the pint: 84 into the sleeve 82, and during subsequent operations these slugs will be discharged from the machine through the openings 88, 8|, 82 and 88. Should these slugs stick together, they will be broken up by the tapered end 81 of the sleeve plug 88 and fallout by gravity through the openings.

The finished blank is shown in Fig. 9 at I88, where it will be noted an opening IN is formed entirely through the body portion thereof. It will also be noted that the flare of the wall or skirt, as shown at 88 in Fig. 8, is reversed in Fig. 9. as shown at I82. Inotherwords. the outer surface of this wall is now slightly tapered inwardly toward its upper end, while the inner surface of the skirt defining the recess I88 is subthe recess. This slight inward displacement of the skirt is eflected when the blank is forced into the die 18 by the piercing punch.

While in most instances the blank will remain in the die at station #8, to be elected by the sleeve 82, it may happen that it will sometimes be stripped from thedie with the withdrawal of the punch 18, and remain on the punch. I have. therefore, provided a stripping sleeve I84 mounted in a stationary arm I88 secured to a part of the frame II of the machine, this sleeve being provided with an opening through which the punch moves. Thus provision is made for stripping the blank either from the die or from .the punch.

The blank as it comes from station #8 is in its finished form. In order to dispose of the finished nut I also provide transfer mechanism to carry it from station #8 to a knock-out station #8, shown on Fig. 1. These transfer fingers are shown diagrammatically at I88, and it is necessary to provide means for removing the completed blank from these fingers. For this purpose 48 a knock-out pin I81 is movably mounted in a sleeve I88 in the arm I88. This sleeve is provided with an adjustable cap H8 at its rear end, which cap is designed to be engaged by an actuating arm I, attached to the gate' of the header, so 80 that as the gate moves forwardly the knock-out pin I81 will be projected between the transfer fingers and elect the nut -therefrom, the.latter falling through a suitable conveyor pipe II2 to any desired place of delivery. The pin I81'is 88 normally held in a rear or retracted position by a spring II8, which acts against the fixed sleeve I88 at one end and against a lock nut H4 on the knock-out pin, this nut also serving to hold the 7 cap H8 in its adjusted position.

o0 While I have shown and described a preferred embodiment of my invention and a preferred method of carrying out myimproved process, will be understood that the invention is not to be limited to all the details shown, nor the process 65 limited to the particular steps described, but both,

are capable of modification and variation within the spirit of the invention and the scope of the claims.

What I claim is:

l. The method of making a nut blank which comprises cutting a workpiece from a length of bar stock, forming in one end of the workpiece a recess surrounded by a cylindrical skirt, and then forcing the workpiece into a polygonal open- 78 ing in a movable die and against and around stantially cylindrical or parallel with the axis of by a skirt, and projecting shoulders between said skirt and faces, and piercing an opening in the workpiece while holding it against movement by said shoulders.

10. The method of making a nut blank which comprises forming a workpiece having a substantially solid body portion with polygonal faces, an end portion provided with a recess surrounded by a skirt, and projecting shoulders between said skirt and faces, forcingsaid workpiece into a die opening against said shoulders, piercing an openflll out the corners between the faces on the body of the workpiece adjacent the skirt.

-3. The method of making a nut blank which comprises cutting a. workpiece from a length of bar stock, forming in one end of the workpiece a recess surrounded by a cylindrical skirt by forcing the workpiece into an opening in a movable die by a punch having a conical recess in its outer end, and then moving the punch and die forwardly to force the work against and around a stationary tool to simultaneously cone one end of the blank and form a recess in the other end thereof. g

4. The method of forming a nut blank from a workpiece having a cylindrical body portion, which comprises'the steps of forcing said workpiece into a polygonal opening in a movable die by means of a punch, then moving both punch and die to force the work against and around a stationary tool to form polygonal faces on the body of the workpiece and fill out the shoulders between said faces at the ends thereof remote from the punch. I

5. The method of forming a nut blank from a workpiece having a cylindrical body portion, which comprises the steps of forcing said workpiece intoa polygonal opening in a movable die by means of a punch, then moving both punch and die as a unit toward a stationary tool having a reduced outer end to force the work against and around the tool and form polygonal faces on the body of the workpiece, with sharply defined corners between said faces at the ends thereof remote from the punch.

6. A machine for forming nut blanks comprising a movably supported die holder, a die carried thereby having an opening therein, said opening having an outer portion of polygonal shape and an innercircular portion, a relatively stationary tool closing the inner end of the die opening, said tool having a recess-forming portion at its outer'end, and a punch cooperating with said die and tool.

'7. A machine for forming nut blanks comprising a movably supported die holder, a die carried thereby having an opening therein, said opening having an outer portion of polygonal shape and an inner circular portion, a relatively stationary tool closing the inner end of the die opening, said tool having a recess-forming portion at its outer end, a punch cooperating with said die and tool, and means urging said die outwardly toward the punch.

8. The method of making a nut blank which comprises forming a workpiece having a recess in one end surrounded bya skirt portion and polygonal outer faces adjacent the other end with shoulders between said faces and skirt portion,

, and piercing an opening in the workpiece while holding it by said shoulders.

9. The method of making a nut blank which comprises forming a workpiece having a substantially solid body portion with polygonal faces, an end portion provided with a recess surrounded ing through the body portion f the workpiece, and then advancing a knock-out sleeve to eject the blank from the die.

11. The method of making a nut blank which comprises forming a workpiece having a substantially solid body portion with polygonal faces, an end portion provided with a recess surrounded by a skirt, and projecting shoulders between said skirt and faces, forcing said blank into a die opening against said shoulders, advancing a punch to pierce a slug out of the body portion of the workpiece to provide an opening therein, and holding said slug against return movement with the punch.

12. Mechanism for forming an opening in a nut blank having a recess in one end, comprising a die having an opemng to receive the blank, a

reciprocable punch movable into the die to remove a slug from the blank, and a sleeve member-adapted to enter a recess in the blank and adapted to enter a recess in the blank and receivethe punched-out slug, and means within said sleeve to engage the slug and hold it against return movement with the punch.

14. Mechanism for forming an opening in a nut blank having a recess in one end, comprising a die having an opening to receive the blank, a reciprocable punch movable into the die to remove a slug from the blank, and a sleeve member adapted to enter a recess in the blank and receive the punched-out slug, said sleeve having a lateral opening therein through which the slug is discharged. l

15. Mechanism for forming an opening in a nutblank having a recess in one end, comprising a die having an opening to receive the blank, a reciprocable punch movable into the die to remove a slug from the blank, a sleeve member adapted to enter a recess in the blank and receive the punched-out slug, and means for advancing the sleeve to strip the blank from the die.

16. Mechanism for forming an openingin a nut blank having a recess in one end, comprising a die having an opening to receive the blank, a reciprocable punch movable into the die to remove a slug from the blank, a sleeve member adapted to enter a recess in the blank and receive the punched-out slug, and means within said sleeve to engage the slug and retain it against return movement with the punch, and said sleeve having a lateral opening therein rearwardly of said means through which the slug is discharged upon subsequent operations of the mechanism.

17. Mechanism for forming an opening in a nut blank having a recess in one end, comprising a die having an opening to receive the blank, a reciprocable punch movable into the die to remove a slug from the blank, a sleeve member adapted to enter a recess in the blank and receivethe punched-out slug, and means within said sleeve to engage the slug and retain it against return "movement with the punch, said sleeve having a lateral opening therein rearwardly of said means through which the slug is discharged upon subsequent operations of the mechanism,

and said sleeve being movable through the die opening to strip the blank from the die.

18. The method of making a nut blank which comprises forming a workpiece having a body portion and-a recess in one end surrounded by a skirt, which comprises holding the workpiece against-movement in a die opening by means en-a by said shoulder while piercing a slug therefrom to form an opening therein. Y

20. Mechanism for forming an opening in a nut blank having a recess in one'end, comprising a die having an opening to receive-the blank, 8.

reciprocable punch movable into the d ie to remove'a slug from the blank, a sleeve. member adapted to enter a. recess in the blank and receive the punched-out slug, and means within said sleeve to engage the slug and hold it against return movement with the punch, said means being fixed with respect to the die.

21. The method of forming a nut blankwhich comprises forming a workpiece-having'a .body portion and a recess in one end, piercing a slug from the body portion of the-blanin-to 'iorm an opening therein while holding'thei-n adie, electing the blank from the die into; engagement holding the workpiece against movement in a die Y with transfer means, and then advancingatool to removethe blankirom said transier means.

RICHARD V 

